Generally, in order to effectively reduce the vibration generated in an engine of a vehicle, the engine is installed in the vehicle through an engine mount. As this engine mount, a rubber mount for isolating and attenuating vibration through the elastic force of rubber and a fluid mount configured to seal hydraulic liquid are generally widely used.
In recent years, a semi-active mount, an active mount, and a magnetorheological fluid (MRF) mount have been developed and used in order to exhibit optimum performance in driving conditions of a vehicle. The semi-active mount and the active mount which are disclosed in Korean Patent Laid-open Publication No. 10-2013-0003749 have the advantage of improving NVH (noise, vibration, harshness) performance by reducing the dynamic characteristics. On the other hand, the MRF mount has the advantage of improving the ride comfort and handling performance by raising the dynamic characteristics.
However, there are problems in that the semi-active mount or the active mount can only control the dynamic characteristics by the on/off method and is bulky, and since the semi-active mount or the active mount transmits the force in the vertical direction, it is difficult to control due to the action of inertia resistance of the magnet.
The MRF mount has problems in that the price of MR fluid is expensive, and when it is left for a long time, the inner steel molecules sink and the dynamic characteristics are not variable.